It seems that around Feb 8, Tracfone had some type of reporting glitch involving their T-Mobile network customers, and wiped out any accumulated data balances. The problem seems isolated to accounts using T-Mobile,
It's unknown whether all T-Mobile users are affected, or just some. Although I haven't seen reports, I would also recommend you check your data balance if you're using the T-Mobile network on any other Tracfone company, including Simple Mobile, Straight Talk, and Net10.
There is recourse if you follow up. Tracfone is aware of the issue (although they will likely deny being aware of it), and escalations seem to be forwarded to agents that know of it. As a fallback, Tracfone usually responds quickly to complaints filed with BBB and the FCC. If you can document what your balance should be, you shouldn't settle for less than that balance-- get what you can from customer service while stating your dissatisfaction, ask for a transaction reference number, and follow up by filing complaints with BBB & FCC.
We have an affected line on Tracfone T-Mobile, with 2.6GB of accumulated data, which now shows only 10MB of available data. I have screenshots, and will follow up today.